Manufacturing processes for automobiles have evolved from one that utilized MIG welding processes, i.e. a welding process in which a line of molten material is deposited by the welder in joining two pieces of metal together. Spot-welding, a process involving the passage of electrical current between two electrodes to melt and join two pieces of metal placed between the electrodes, is being utilized in a greater degree in the manufacturing of automotive vehicles. Spot-welding requires a frame design that is conducive to being manufactured using the spot-welding process. For example, if two tubular members are being spot-welded, access to the adjoining walls of the two tubular members by the spot-welder electrodes must be provided.
The joinder of hydroformed frame members presents a problem for frame construction in automobiles. If the frame members are positioned in a parallel orientation, the contiguous sides of the two frame members can be spot-welded together with the electrodes being inserted through openings formed during the hydroforming process in the respective opposing sides of the frame members.
Since hydroformed frame members are tubular in configuration, the frame members have open ends. Therefore, welding the connection of a frame member that is butted against a lateral side of another frame member presents a welding problem that is conventionally solved by MIG welding processes with the edges of the butted frame member being welded to the sides of the adjoining frame member. If the frame member being butted against the lateral side of the other frame member is physically smaller that the other frame member, the smaller frame member can be inserted into an opening formed in the other frame member so that the smaller frame member butts or aligns with the opposing surface of the larger frame member and the respective sides of the frame members can be spot-welded together if the frame members are sized appropriately. However, such welding techniques do not work if the two frame members are not sized to snuggly fit together before being spot-welded.
Accordingly, it would be desirable to provide a system and welding process in which spot-welding techniques could be utilized to weld together frame members that are butted together with at least one end of a frame member to be welded to anther frame member.